Download or read book Visual Cortical Mechanisms of Motion Perception and Navigation written by Christopher Pack and published by . This book was released on 1999 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dynamics of Visual Motion Processing written by Guillaume S. Masson and published by Springer Science & Business Media. This book was released on 2009-12-02 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt: Motion processing is an essential piece of the complex brain machinery that allows us to reconstruct the 3D layout of objects in the environment, to break camouflage, to perform scene segmentation, to estimate the ego movement, and to control our action. Although motion perception and its neural basis have been a topic of intensive research and modeling the last two decades, recent experimental evidences have stressed the dynamical aspects of motion integration and segmentation. This book presents the most recent approaches that have changed our view of biological motion processing. These new experimental evidences call for new models emphasizing the collective dynamics of large population of neurons rather than the properties of separate individual filters. Chapters will stress how the dynamics of motion processing can be used as a general approach to understand the brain dynamics itself.
Download or read book The Brain s Sense of Movement written by Alain Berthoz and published by Harvard University Press. This book was released on 2000 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt: This interpretation of perception and action allows Alain Berthoz to focus on psychological phenomena: proprioception and kinaesthesis; the mechanisms that maintain balance and co-ordination actions; and basic perceptual and memory processes involved in navigation.
Download or read book Visual Cortical Mechanisms of Movement Perception written by Guy A. Orban and published by . This book was released on 1975 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High level Motion Processing written by Takeo Watanabe and published by MIT Press. This book was released on 1998 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt: The contributors to this book focus on such key aspects of motion processing as interaction and integration between locally measured motion units, structure from motion, heading in an optical flow, and second-order motion. They also discuss the interaction of motion processing with other high-level visual functions such as surface representation and attention.
Download or read book Vision and Movement written by and published by . This book was released on 1996 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cortical Neural Network Models of Visual Motion Perception for Decision Making and Reactive Navigation written by Michael Beyeler and published by . This book was released on 2016 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: Animals use vision to traverse novel cluttered environments with apparent ease. Evidence suggests that the mammalian brain integrates visual motion cues across a number of remote but interconnected brain regions that make up a visual motion pathway. Although much is known about the neural circuitry that is concerned with motion perception in the Primary Visual Cortex (V1) and the Middle Temporal area (MT), little is known about how relevant perceptual variables might be represented in higher-order areas of the motion pathway, and how neural activity in these areas might relate to the behavioral dynamics of locomotion.The main goal of this dissertation is to investigate the computational principles that the mammalian brain might be using to organize low-level motion signals into distributed representations of perceptual variables, and how neural activity in the motion pathway might mediate behavior in reactive navigation tasks. I first investigated how the aperture problem, a fundamental conceptual challenge encountered by all low-level motion systems, can be solved in a spiking neural network model of V1 and MT (consisting of 153,216 neurons and 40 million synapses), relying solely on dynamics and properties gleaned from known electrophysiological and neuroanatomical evidence, and how this neural activity might influence perceptual decision-making. Second, when used with a physical robot performing a reactive navigation task in the real world, I found that the model produced behavioral trajectories that closely matched human psychophysics data. Essential to the success of these studies were software implementations that could execute in real time, which are freely and openly available to the community. Third, using ideas from the efficient-coding and free-energy principles, I demonstrated that a variety of response properties of neurons in the dorsal sub-region of the Medial Superior Temporal area (MSTd) area could be derived from MT-like input features. This finding suggests that response properties such as 3D translation and rotation selectivity, complex motion perception, and heading selectivity might simply be a by-product of MSTd neurons performing dimensionality reduction on their inputs. The hope is that these studies will not only further our understanding of how the brain works, but also lead to novel algorithms and brain-inspired robots capable of outperforming current artificial systems.
Download or read book Visual Detection of Motion written by Andrew T. Smith and published by . This book was released on 1994 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt: The brain's ability to detect movement within the retinal image is crucial not only for determining the trajectories of moving objects, but also for identifying and interpreting image motion resulting from eye and head movements. This book summarizes our knowledge of how information about image motion is encoded in the brain. Key Features * Valuable reference source for those involved in the rapidly expanding area of motion perception * Strong emphasis on integration of physiological, computation, and psychophysical approaches * Topics include: * Principles of local motion detection * Inputs to local motion detectors * Integration of motion signals * Higher-order interpretation of motion * Motion detection and eye movements
Download or read book Visual motion and self motion processing in the human brain MPI Series in Biological Cybernetics Bd 31 written by Elvira Fischer and published by Logos Verlag Berlin GmbH. This book was released on 2011 with total page 127 pages. Available in PDF, EPUB and Kindle. Book excerpt: For the successful recognition of objective, `real' motion based on visual cues it is necessary to take self-induced motion signals into account, such as those induced by eye-movements. During a series of fMRI studies we measured responses of visual and parietal regions to motion cues derived from (a) retinal motion, (b) eyemovements (visual pursuit) and (c) objective, (real) motion. We show that the recently described cingulate sulcus visual area (CSv) is not, as implied before, primarily driven by 3D self-motion cues but favoured 2D translational coherent motion over 3D expanding flow fields. Further, we found that V3A is capable of integrating retinal motion with eye-movements, thus allowing V3A to respond to object motion independent of retinal motion. This allowed us to define a new functional localizer for area V3A. Finally, we showed that activity in the foveal representation of the early visual cortex is driven by a combination of retinal input and by error signals as hypothesized by of Rao and Ballard (1999) for predictive coding. Taken together, this work provides evidence that regions V3A and CSv are key regions concerning visual self-motion processing and that early visual regions might be modulated by feedback from higher motion processing regions.
Download or read book The Motion Aftereffect written by George Mather and published by MIT Press. This book was released on 1998 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: Motion perception lies at the heart of the scientific study of vision. The motion aftereffect (MAE) is the appearance of directional movement in a stationary object or scene after the viewer has been exposed to viusal motion in the opposite direction. For example, after one has looked at a waterfall for a period of time, the scene beside the waterfall may appear to move upward when one's gaze is transfered to it. Although the phenomenon seems simple, research has revealed copmlexities in the underlying mechanisms, and offered general lessons about how the brain processes visual information. In the 1990s alone, more than 200 papers have been published on MAE, largely inspired by improved techniques for examining brain electrophysiology and by emerging new theories of motion perception.
Download or read book Cortical Mechanisms of Vision written by Michael Jenkin and published by Cambridge University Press. This book was released on 2009-07-09 with total page 459 pages. Available in PDF, EPUB and Kindle. Book excerpt: The advent of sensors capable of localizing portions of the brain involved in specific computations has provided significant insights into normal visual information processing and specific neurological conditions. Aided by devices such as fMRI, researchers are now able to construct highly detailed models of how the brain processes specific patterns of visual information. This book brings together some of the strongest thinkers in this field, to explore cortical visual information processing and its underlying mechanisms. It is an excellent resource for vision researchers with both biological and computational backgrounds, and is an essential guide for graduate students just starting out in the field.
Download or read book Motion Vision written by Johannes M. Zanker and published by Springer Science & Business Media. This book was released on 2011-06-28 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt: In six parts, this book considers the extent to which computational, neural, and ecological constraints have shaped the mechanisms underlying motion vision: - Early Motion Vision - Motion Signals for Local and Global Analysis - Optical Flow Patterns - Motion Vision in Action - Neural Coding of Motion - Motion in Natural Environments Each topic is introduced by a keynote chapter which is accompanied by several companion articles. Written by an international group of experts in neurobiology, psychophysics, animal behaviour, machine vision, and robotics, the book is designed to explore as comprehensively as possible the present state of knowledge concerning the principal factors that have guided the evolution of motion vision.
Download or read book Inhibitory Mechanisms in Visual Motion Perception written by Sandra Arranz Paraíso and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The world around us is constantly changing, with multiple objects in the environment changing position, luminance, and color. These objects can also move on static or in motion backgrounds, with the same or different speed, in opposite direction, etc. Our Visual System can segregate figures from the background and thus extract information about objects in complex environments. Understanding how humans process motion is one of the most relevant and sophisticated problems in visual perception (see review of Nishida, 2011). The functional characteristics of the underlying mechanisms are not completely known, in particular, the role of the inhibitory mechanisms in motion perception. Therefore, the main goal of this Thesis is the psychophysical characterization of the functional properties of two inhibitory mechanisms involved in visual motion perception. It has traditionally been proposed that the antagonistic center-surround mechanisms are implicated in the segregation of the figure from the background (Lappin & Tadin, 2004;Tadin et al., 2019). The normal functioning of these mechanisms causes difficulties in perceiving large moving objects at high contrast (Derrington & Goddard, 1989). However, at low contrast, the larger the size of the object, the easier it is to detect its motion (Tadin etal., 2003). To explain these results, it is assumed that in these mechanisms, when the stimulus is large and has high contrast, the peripheral region suppresses or inhibits the activation of the center, and for low contrast, it facilitates the activation of the center. The same results have been found by analyzing the response of neurons with antagonistic center-surround receptive fields present in the medial temporal (MT) area of the visual cortex (Pack, Hunter & Born, 2005) and in the medial superior temporal (MST) area (Eifuku & Wurtz, 1998). The shape of these receptive fields is not fully characterized, although recent studies suggest an elongated spatial configuration in the direction of movement (Serrano-Pedraza, Hogg & Read, 2011), in agreement with physiological evidence (Xiao et al., 1997)...
Download or read book The Active Control of Self Movement Perception Neuronal Mechanisms and Cognitive Aging written by Michael Simon Jacob and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Self-movement creates a radial pattern of optic flow that tells us where we are going. Recent studies have shown that the processing of visual motion is actively controlled by frontal-parietal cortical networks to satisfy the demands of ongoing behavior. Navigation-related visual motion perceptual deficits in aging and Alzheimer's disease (AD) suggest a systems level disruption of optic flow processing in these conditions. We have now examined this system using human evoked potentials and probed the underlying neuronal mechanisms using monkey single neuron physiology. In our studies of aging and AD, we combine a continuous visual discrimination task with simultaneous visual motion and word stimulus streams to assess task effects on stimulus evoked cortical activity. We find that the cognitive control of motion and word processing are fundamentally different in aging and AD. Impairments in verbal fluency among our AD patients and impairments in optic flow perceptual thresholds among our older adult subjects are associated with selective reductions in cortical responsiveness to word and optic flow stimuli, respectively. Thus, diagnostic criteria for AD may not appropriately consider impairments in visuospatial processing. Monkeys trained in a memory guided steering task show single neurons with task-dependent optic flow processing in cortical areas MST and LIP. One third of MST neurons show task effects on basic neuronal response properties. In contrast, LIP neurons show minimal optic flow stimulus selectivity but pronounced task effects on their responses. Both MST and LIP show evidence of cognitive signals related to motor planning just prior to steering. These results suggest that posterior parietal cortical areas form a distributed network which is dynamically shaped by task demands. Despite species and methodological differences, the dynamics of cortical activity in humans and monkeys show sensory signals that are followed shortly by cognitive signals to actively modulate self-movement perception. In young adult human subjects and monkey single neurons, we see obligate optic flow processing in all task conditions. In older adult humans, we see a loss of obligate optic flow responsiveness which may suggest a selective vulnerability of visuospatial processing networks in cognitive aging.
Download or read book The Senses A Comprehensive Reference written by and published by Academic Press. This book was released on 2020-09-30 with total page 5215 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Senses: A Comprehensive Reference, Second Edition, Seven Volume Set is a comprehensive reference work covering the range of topics that constitute current knowledge of the neural mechanisms underlying the different senses. This important work provides the most up-to-date, cutting-edge, comprehensive reference combining volumes on all major sensory modalities in one set. Offering 264 chapters from a distinguished team of international experts, The Senses lays out current knowledge on the anatomy, physiology, and molecular biology of sensory organs, in a collection of comprehensive chapters spanning 4 volumes. Topics covered include the perception, psychophysics, and higher order processing of sensory information, as well as disorders and new diagnostic and treatment methods. Written for a wide audience, this reference work provides students, scholars, medical doctors, as well as anyone interested in neuroscience, a comprehensive overview of the knowledge accumulated on the function of sense organs, sensory systems, and how the brain processes sensory input. As with the first edition, contributions from leading scholars from around the world will ensure The Senses offers a truly international portrait of sensory physiology. The set is the definitive reference on sensory neuroscience and provides the ultimate entry point into the review and original literature in Sensory Neuroscience enabling students and scientists to delve into the subject and deepen their knowledge. All-inclusive coverage of topics: updated edition offers readers the only current reference available covering neurobiology, physiology, anatomy, and molecular biology of sense organs and the processing of sensory information in the brain Authoritative content: world-leading contributors provide readers with a reputable, dynamic and authoritative account of the topics under discussion Comprehensive-style content: in-depth, complex coverage of topics offers students at upper undergraduate level and above full insight into topics under discussion
Download or read book Perception written by R. Held and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 986 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume was designed to focus on the problems of perception and originally was to have been solely edited by Professor Hans-Lukas Teuber who was a member of the editorial board which initiated production of the Handbook. Accordingly, he issued invitations to a number of researchers III perception asking them to contribute chapters written in a style described III his words: " . . . Ire hope that no author lI'ill feel COl/strained to undertake a major search of the literature: he could In'ite, instead. on an area in which he has been quite actire himse?t~ and II'here most of the issues are immediately obt"ious to him. In this Iray, the IITiting of the chapter should be cnjoyable rather than a chore . . it should result in a personal account of the state of a given area rather than in an encyclopedic treatise . . . the field deserves this sort of summary ret'iell", particularly (f it is pointed toward the future and speeds the convergence of det'elopments in sensory physiology and psychological studies of perception, " With the growing burden of national and international commitments includ ing departmental headship, Professor Teuber felt that it would be wise to share the editorial responsibilities for this volume and accordingly, asked Professors Richard Held and Herschel Leibowitz to co-edit the volume with him in the same spirit as outlined in his invitation to authors. They agreed to help in this task.
Download or read book Spatial Processing in Navigation Imagery and Perception written by Fred W. Mast and published by Springer Science & Business Media. This book was released on 2007-06-13 with total page 446 pages. Available in PDF, EPUB and Kindle. Book excerpt: The processing of spatial information is an increasingly important topic, especially in recent few years, with new findings emerging from such diverse disciplines as cognitive neuroscience; cognitive psychology; sensorimotor integration; neuropsychology and neuroanatomy. Bringing together contributions from a group of internationally highly renowned researchers from across these disciplines, this book offers a state-of-the-art platform on which the latest developments in spatial processing are presented.
